In the letter, Obama said he would meet with her in Flint on Wednesday, May 4, when he tours the city.

Mari, known as "Little Miss Flint," told the President about her efforts to bring attention to the city's water crisis and she asked if she could meet Obama and First Lady Michelle Obama during an upcoming trip to Washington, D.C.

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"I will be riding a bus to Washington, D.C. to watch the congressional hearings of our Governor Rick Snyder. I know this is probably an odd request but I would love for a chance to meet you or your wife," Mari wrote. "My mom said chances are you will be too busy with more important things, but there is a lot of people coming on these buses and even just a meeting from you or your wife would really lift people's spirits."

Obama wrote the girl back to let her know he will meet with her when he comes to Flint for an in-person briefing on federal efforts responding Flint residents.

"You're right, Presidents are often busy, but the truth is, in America, there is no more important title than citizen," Obama said.

"Letters from kids like you are what make me so optimistic for the future. I hope to meet you next week, 'Little Miss Flint,'" he added.

While there, Obama will also speak with members of the Flint community.